Myrmeleontiformia
Myrmeleontiformia is a lacewing suborder in the order . The of the Neuroptera has been explored using sequences, and while issues remain for the group as a whole (the " " being ), the Myrmeleontiformia is generally agreed to be . The antlions are a group of about 2,000 of in the Myrmeleontidae, known for the fiercely habits of their e, which in many species dig pits to trap passing s or other prey. The adult insects are less well known, as they mostly fly at dusk or after dark, and may be mistakenly identified as or ; they are sometimes known as antlion lacewings, and in North America, the larvae are sometimes referred to as doodlebugs because of the strange marks they leave in the sand. Antlions have a worldwide distribution. The greatest diversity occurs in the tropics, but a few species are found in cold- locations, one such being the European . They most commonly occur in dry and sandy habitats where the larvae can easily excavate their pits, but some larvae hide under debris or ambush their prey among leaf litter. Antlions are poorly represented in the fossil record. is generally accepted to be a group, and within the , the antlions' closest living relatives are thought to be the (Ascalaphidae). The predatory actions of the larvae have attracted attention throughout history, and antlions have been mentioned in literature since classical times. Etymology The exact meaning of the name "antlion" is uncertain. It has been thought to refer to ants forming a large percentage of the prey of the insect, the suffix "lion" merely suggesting destroyer or hunter. In any case, the term seems to go back to . The antlion larva is often called a "doodlebug" in because of the odd winding, spiralling trails it leaves in the sand while relocating, which look as if someone has been . The of the Myrmeleo – and thus, the family as a whole – is derived from léon (λέων) "lion" + mýrmex (μύρμηξ) "ant", in a of the names common across Europe. In most European and Middle Eastern languages, at least the larvae are known under the local term corresponding to "antlion". Description Antlions can be fairly small to very large ns, with wingspans ranging from . The African genus contains some of the largest examples. is the largest European species, with an wingspan, and most North American species approach this size. The adult has two pairs of long, narrow, multiveined, translucent and a long, slender . Although they somewhat resemble or , they belong to a different of . Antlion adults are easily distinguished from damselflies by their prominent, apically clubbed which are about as long as the head and combined. Also, the pattern of wing venation differs, and compared to damselflies, the adults are very feeble fliers and are normally found fluttering about at night in search of a mate. Adult antlions are typically , and rarely seen by day. Males of most species have a unique structure, a bristle-bearing knob known as a "pilula axillaris", at the base of the rear wing. The abdomen in males is usually longer than in females and often has an extra lobe. The tip of the abdomen of females shows greater variation than that of males, depending perhaps on sites, and usually bears tufts of bristles for digging and a finger-like extension. The antlion has a robust body, a very plump abdomen, and a thorax bearing three pairs of walking legs. The forms a slender mobile "neck" for the large, square, flattened head, which bears an enormous pair of sickle-like jaws with several sharp, hollow projections. The jaws are formed by the ; the mandibles each contain a deep groove over which the maxilla fits neatly, forming an enclosed canal for injecting to immobilise the victim, and s to digest its soft parts. The larva is clad in forward-pointing bristles which help it to anchor itself and exert greater traction, enabling it to subdue prey considerably larger than itself. Antlion larvae are unusual among insects in lacking an . All the waste generated during the larval stage is stored; some is used to spin the silk for the and the rest is eventually voided as at the end of its l stage. Distribution There are about 2,000 species of antlion found in most parts of the world, with the greatest diversity being in warmer areas. The best known species are those in which the larvae dig pits to trap their prey, but by no means do all species do this. Antlions live in a range of usually dry habitats including open woodland floors, -clad s, hedge bases, river banks, road verges, under raised buildings and in vacant lots. Life-cycle }} Apart from pit-trap-forming taxa, the biology of members of the family Myrmeleontidae, to which the antlions belong, has been little studied. The life-cycle begins with oviposition ( -laying) in a suitable location. The female antlion repeatedly taps the prospective laying site with the tip of her abdomen and then inserts her ovipositor into the and lays an egg. Depending on the species and where it lives, the larva either conceals itself under leaves, debris or pieces of wood, hides in a crack or digs a funnel-shaped pit in loose material. As s, catching prey is risky because food arrives unpredictably and, for those species that make traps, maintaining one is costly; the larvae therefore have low metabolic rates and can survive for long periods without food. They can take several years to complete their life-cycle; they mature faster with plentiful food, but can survive for many months without feeding. In cooler climates they dig their way deeper and remain inactive during the winter. When the larva attains its maximum size, it tes and undergoes . It makes a globular cocoon of sand or other local substrate stuck together with fine spun from a slender at the rear end of the body. The cocoon may be buried several centimetres deep in sand. After completing its transformation into an adult insect over the course of about one month, it emerges from the case, leaving the pupal integument behind, and works its way to the surface. After about twenty minutes, the adult's wings are fully opened and it flies off in search of a mate. The adult is considerably larger than the larva as antlions exhibit the greatest disparity in size between larva and adult of any type of insect. This is by virtue of the fact that the of the adult is extremely thin and flimsy, with an exceptionally low . The adult typically lives for about 25 days, but some insects survive for as long as 45 days. Ecology Antlion e eat small arthropods – mainly s – while the adults of some species eat and , and others are predators of small arthropods. In certain species of Myrmeleontidae, such as , the larva, although resembling that of Myrmeleon structurally, makes no pitfall trap, but hides in in a hole in a tree and seizes passing prey. In Japan, larvae lurk on the surface of rocks for several years while awaiting prey; during this time they often become coated with , and have been recorded at densities of up to 344 per square metre. The larva is a voracious predator. Within a few minutes of seizing its prey with its jaws and injecting it with and s, it begins to suck out the digestion products. The larva is extremely sensitive to ground vibrations, the low-frequency sounds made by an insect crawling across the ground; the larva locates the source of the vibrations by the differences in timing of the arrival of s detected by s, tufts of hairs on the sides of the two hindmost thoracic segments. In trap-building species, an average-sized larva digs a pit about 2 in (5 cm) deep and 3 in (7.5 cm) wide at the edge. This behavior has also been observed in the ( ), whose larvae dig the same sort of pit to feed on ants. Having marked out the chosen site by a circular groove, the antlion larva starts to crawl backwards, using its abdomen as a plough to shovel up the soil. By the aid of one front leg, it places consecutive heaps of loosened particles upon its head, then with a smart jerk throws each little pile clear of the scene of operations. Proceeding thus, it gradually works its way from the circumference towards the center. As it slowly moves round and round, the pit gradually gets deeper and deeper, until the slope angle reaches the (that is, the steepest angle the sand can maintain, where it is on the verge of collapse from slight disturbance), and the pit is solely lined by fine grains. By digging in a spiral when constructing its pit, the antlion minimises the time needed to complete the pit. When the pit is completed, the larva settles down at the bottom, buried in the soil with only the jaws projecting above the surface, often in a wide-opened position on either side of the very tip of the cone. The steep-sloped trap that guides prey into the larva's mouth while avoiding crater avalanches is one of the simplest and most efficient traps in the animal kingdom. The fine grain lining ensures that the avalanches which carry prey are as large as possible. Since the sides of the pit consist of loose sand at its angle of repose, they afford an insecure foothold to any small insects that inadvertently venture over the edge, such as ants. Slipping to the bottom, the prey is immediately seized by the lurking antlion; if it attempts to scramble up the treacherous walls of the pit, it is speedily checked in its efforts and brought down by showers of loose sand which are thrown at it from below by the larva. By throwing up loose sand from the bottom of the pit, the larva also undermines the sides of the pit, causing them to collapse and bring the prey with them. Thus, it does not matter whether the larva actually strikes the prey with the sand showers. Antlion larvae are capable of capturing and killing a variety of s and other s, and can even subdue small s. The projections in the jaws of the larva are hollow and through this, the larva sucks the fluids out of its victim. After the contents are consumed, the dry carcass is flicked out of the pit. The larva readies the pit once again by throwing out collapsed material from the center, steepening the pit walls to the angle of repose. Antlion larvae require loose soil, not necessarily but often sand. Antlions can also handle larger granular material which is filtered out of the soil during pit construction. The larvae prefer dry places protected from the rain. When it first hatches, the tiny larva specialises in very small insects, but as it grows larger, it constructs larger pits, and thus catches larger prey, sometimes much larger than itself. Other arthropods may make use of the antlion larva's ability to trap prey. The larva of the Australian horsefly ( ) lives in antlion (for example ) pit traps and feeds on the prey caught, and the female ( ) purposefully allows itself to be trapped so that it can parasitise the antlion larva by ovipositing between its head and thorax. Evolution fossil wing of ( )}} The closest living relatives of antlions within the are the (Ascalaphidae); the are more distantly related. The extinct and are considered likely to be stem groups in the Myrmeleontiformia . The of the Neuroptera has been explored using sequences, and while issues remain for the group as a whole (the " " being ), the Myrmeleontiformia is generally agreed to be , giving the following : |1= (formerly in "Hemerobiiformia") |2= (mantidflies) |2= (moth lacewings) |2= (green lacewings) }} }} |label2= |2= (split-footed lacewings) |2= |2= (owlflies) }} }} }} }} }} The are shown below; a few genera, mostly , are of uncertain or position. The fossil record of antlions is very small by neuropteran standards. However, some fossils attest to the antlions' origin more than 150 million years ago. These were at one time separated as the Palaeoleontidae, but are now usually recognized as early antlions. There is little consensus regarding the supra-generic classification within the Myrmeleontidea, but the following four subfamilies (with select genera) are accepted by many researchers: * ** * ** Navás, 1912 ** ** Esben-Petersen, 1918 *** (European antlion) ** Banks, 1913 *** *** Australia ** *** Africa ** * (including Araripeneurinae) ** * ** The following subfamilies have been recognized by some taxonomists: * (otherwise in Myrmeleontinae) * (otherwise in Myrmeleontinae) * * * * (otherwise in Myrmeleontinae) * (otherwise in Myrmeleontinae) * Antlions of uncertain systematic position are: * (fossil) * * Gallery File:Antlion doodles.jpg|Antlion larva trails (doodles) in sand File:2015.10-434-146bp antlion(unidentified sp.,adult,L(wing tip-antnena tip)4.8cm) DD11.176086,-4.335053@Bobo-Dioulasso,BF thu29oct2015-1054h.jpg|Thorax and head (with club-shaped antenna) of antlion adult File:Antlion1 by Jonathan Numer.jpg|Larva File:Formicaleone.jpg|20x closeup of larva File:Antlion.ogv|Video of antlion larva trying to catch prey with sand traps and eating a small File:Antlion video.ogv|Video of a larva trapping an ant by throwing sand at it , from the of Jacob Meydenbach, 1491}} In culture and folklore In popular folklore in the southern United States, people recite a poem or chant to make the antlion come out of its hole. Similar practices have been recorded from Africa, the Caribbean, China and Australia. The was a mythical ant-lion hybrid written about in the 2nd century AD , where animal descriptions were paired with Christian morals. The ant-lion as described was said to starve to death because of its dual nature – the lion nature of the father could , but the ant half from the mother could only , thus the offspring could not eat either and would starve. It was paired with the Biblical verse . The fictional ant-lion of Physiologus is probably derived from a misreading of Job 4:11. The French naturalist wrote that "The Ant-lion makes a slanting funnel in the sand. Its victim, the Ant, slides down the slant and is then stoned, from the bottom of the funnel, by the hunter, who turns his neck into a catapult." Antlions appear as antagonists in the 1991 , , the series, , , , and in the video game series. The evolution line is based on an antlion. In , an antlion is featured as a boss. The fictional from the is often compared to the real-life antlion. It also appears as a predator in the movie . Notes References Category:Tree of life